1. Field of the Invention
The present invention relates to an ink-jet head that ejects ink on a recording medium for recording and a method of manufacturing the same.
2. Description of Related Art
An ink-jet head disclosed in a Japanese Patent Unexamined Publication No. 2005-22148 includes a unit having a number of nozzles and pressure chambers communicating with the respective nozzles. To a surface of the unit in which the pressure chambers are formed are fixed four piezoelectric sheets. Flexible printed circuit boards (FPC) are respectively fixed to each of the piezoelectric sheets. The FPC is one type of a flexible print cable. The piezoelectric sheets function as actuators. The piezoelectric sheets are formed on surfaces thereof with individual electrodes corresponding to the respective pressure chambers. The respective individual electrodes are electrically connected to the FPC via conductive lands adhered thereto. When a driving signal is supplied to the individual electrodes through the FPC, the volumes of the pressure chambers corresponding to the individual electrodes are changed and pressure is applied to ink in the corresponding pressure chambers. Thereby, the ink is ejected to a recording medium such as paper from the nozzles, so that an image is recorded on the recording medium.
The surfaces of the piezoelectric sheets are formed with common electrodes in addition to the individual electrodes. The common electrodes are formed at four corners of the piezoelectric sheet having a trapezoidal shape. Each of the common electrodes is electrically connected to an inner electrode formed in the piezoelectric sheet. The common electrodes are also adhered to the conductive lands, likewise the individual electrodes. The common electrodes are electrically connected to the FPC via the lands.
The vicinity of a leading end of the FPC is fixed to the upper surface of the piezoelectric sheet and a leading end side of the FPC is approximately identical to an upper base, i.e., short side of the piezoelectric sheet having a trapezoidal shape. The FPC is drawn-out into an outside, beyond the lower base, i.e., long side of the piezoelectric sheet. A part of the FPC, which is closer to the base thereof than the lower base of the piezoelectric sheet, is not fixed to the piezoelectric sheet. The lands adhered to the two common electrodes close to the lower base are disposed at positions closer to the lower base than the lands adhered to any individual electrodes.
When fixing the FPC to the piezoelectric sheet, soldering is applied to terminals formed on the FPC and heat is applied to the terminals and the lands while aligning the respective terminals and the lands, thereby adhering the terminals and the lands.